Impression cylinder pressure setting mechanism



y 1961 H. E. PEYREBRUNE 2,982,206

IMPRESSION CYLINDER PRESSURE SETTING MECHANISM Filed Feb. 24,1958 2Sheets-Sheet 1 INVENTOR. HENRI a. PEYREBRUNE ATTORNEYS United StatesPatent llVIPRESSION CYLINDER PRESSURE SETTING MECHANISM Henri E.Peyl'ebrune, River Forest, 11]., assignor to Miehle-Goss-Dexter,Incorporated, Chicago, Ill., a corporation of Delaware Filed Feb. 24,1958, Ser. No. 716,903

' 3 Claims. (Cl. 101-283) cylinder when said cylinder is in itsoperative or impression position.

In flat bed and cylinder presses, which may be either printing pressesor die cutting and creasing presses, the

printing or die cutting form to be reproduced is supported on the bedand suitable mechanism is provided to impart continuous reciprocatingmotion to the latter. During the operative stroke of the bed theimpression cylinder is moved to its operative or impression position forcoaction with the form to effect an impression on sheet material passedtherebetween and on the return or inoperative stroke of the bed thecylinder continues to rotate in the same direction but it is raised toan inoperative position so as to provide clearance for the form.

In order to print an impression or die cut and crease a sheet,considerable pressure must be exerted between the impression cylinderand the form during the operative stroke of the bed. The amount ofpressure required, however, is dependent to a great extent upon thespecific requirements of each particular form to be processed. It

i is essential, therefore, that convenient and accurate means beprovided for adjusting the impression pressure in ac- 2,982,206 PatentedMay 2, 1961 ice Elf the coacting members, can be properly compensatedBecause the known pressure control mechanisms do not incorporate meansfor preloading the respective parts against the force of the impression,press manufacturers have attempted to accomplish a similar result bybringing the bed and cylinder bearers into engagement before the formreaches the impression position. This is done by extending the bedbearers forwardly beyond the leading edge of the form so that theyengage the cylinder bearers and thereby compress the pressure controlmembers before the actual impression starts. The space available forthis purpose, however, is extremely' limited and although it has provenadequate whereby to take up all I of the clearances, it is notsufficient to permit the members to be fully compressed before theimpression begins. As a result, the slight relative movement of thecylinder due to the continuing compression of the control members afterthe impression has started, causes a variation in density of theimpression throughout the lengthof each sheet.

It will be appreciated that the overall movement of the impressioncylinder resulting from clearances and the compression of the variouscontrol elements, is relatively infinitesimal. However, incredibly,small changes involving one or two thousandths of an inch can mean i thedifference between high quality work and just mediocre prints and,therefore, the provision of means whereby relative motion of theimpression cylinder after the impression has started, can be eliminatedor substantially reduced, is extremely important.

It is a primary object of this invention, therefore, to provideimpression pressure adjusting mechanism which can be adjustedconveniently and with the utmost precision and which incorporatesmechanism whereby at least some of the adjustable members can bepreloaded Y against the force of impression.

cordance with the specific requirements of each job so 7 that it can bemaintained at a minimum and thereby avoid imposing unnecessary andexcessive strains on the mechamsm.

In addition, such adjusting mechanism should incorporate means forremoving all clearances between the coacting members and forprecompressing said members prior to the cylinder and form going onimpression to preclude any relative movement between the members afterthe impression has started which will have an adverse efli'ect upon thequality of the work produced.

Heretofore, it has been standard practice to provide relatively heavyjack screws on each side of the press which are adjustable whereby tovary and thereafter maintain the pressure setting of the impressioncylinder. Such means, however, cannot be calibrated with any degree ofaccuracy and thus numerous readjustments are required and considerabletime is Wasted each time a pressure change 'is made before a precisecorresponding setting is obtained at both ends of the cylinder.

It is also known to utilize adjustable eccentric means to control andadjust the pressure setting of the impression cylinder. Such devicesprovide a relatively high degree of accuracy as compared to the jackscrews, however not any of the known devices incorporate means forpreloading the coacting members against the force of impression.Therefore, numerous readjustments invariably are required beforerelative movement of the cylinder,

due tothe take up of the clearances and the compression Another objectof this invention resides in the provision of a rotatable eccentricmember for eifecting impression pressure adjustment and which presents amaximum surface area to resist the force of impression.

A further object is to provide simple and efficient means for effectingadjustment of the eccentric pressure control member and which meansserve the dual function of preloading said member against the force ofimpression.

Other objects and advantages will become apparent from the followingdescription and accompanying drawings wherein:

Figure 1 is a side elevation of the cylinder assembly of a flat bed andcylinder press;

Figure 2 is an enlarged sectional view taken substantially along lineIIII of Figure 1;

Figure 3, is a sectional view along line lIIIII of Figure 2; and

Figure 4-, is a partial view of the mechanism for retaining the pivotpins in their operative positions.

In Figure 1, the invention is illustrated as embodied in a conventionalflat bed and cylinder press wherein an impression cylinder 10 is adaptedto coact with areciprocating bed 1'1 to effect impressions on sheets offormed in the side faces of the bearing block so as to maintain itagainst any lateral movement while permitting it to move vertically uponactuation of the cylinder control mechanism.

Mounted below the bearing block 16 are a pair of compression springs 19.These springs are seated in the frame member 14 and are adapted to exertconstant pressure against the bottom face of the bearing block tendingto maintain the latter and thus the impression cylinder in its raised orinoperative position. When the cylinder is moved downwardly to itsoperative position as shown in Figure 1, the springs 19 are compressedand serve to return the cylinder to its raised position upon return ofthe cylinder actuating mechanism to its inactive position. Guide rods 20maintain the springs against lateral displacement and are seated in theframe member 14. The upper ends of said rods project into openingsprovided therefor in the bearing block and it will be noted that therecesses in the bearing block are deep enough to permit verticalmovement of the said block through its maximum stroke withoutinterference with said guides.

Movement of the cylinder to its operative or impression position againstthe pressure of the springs 19 is effected by means of an oscillatableeccentric cylinder actuating member 21 which is located above thebearing block 16 between a cylinder control block 22 and a spacer block23. As shown in Figures 1 and 2, the actuating member 21 is formed withbearing surfaces 24 and 25 adjacent its lateral edges. These surfacesare concentric with respect to the axis A of said member and are seatedin the control block 22, the bottom surface of which is formed with aconcave semi-cylindrical seat having the same radius as the bearingsurfaces 24 and 25. Intermediate the bearing surfaces 24 and 25, and onthe lower half of the actuating member 21 is a curved surface 26 whichis formed eccentric with respect to the bearing surfaces 24 and 25 aboutthe axis B. This surface in turn is seated in a correspondingly curvedseat formed in the upper edge of the block 23 which is mounted on thetop surface of the bearing block 16 and is adapted to slide laterallythereon, as viewed in Fig. 1, when the cylinder actuating member 21 isoscillated.

Thus the cylinder actuating member 21 is, in effect, a toggle which,upon being moved to the rotative position as shown in Figure 1, whereinthe respective axes A and B are coincident With a vertical plane throughthe axis of the journal 15, moves the bearing block 16 downwardlyagainst the pressure of the springs 19 to its impression position. Whenthe member 21 is rotated clockwise, as viewed in Figure l, the axis B ismoved out of said plane, thus relieving the pressure on the bearingblock 16 and permitting the springs 19 to raise the cylinder to itsinoperative position.

Oscillating motion is imparted to the member 21 for the purpose ofraising and lowering the impression cylinder, through an arm 27 which isformed integral with said member and which has pivotally connected toits free end a connecting link 28. The opposite end of the latter memberis connected to suitable actuating mechanism, not shown, but which isarranged to oscillate the member 21 in timed relation to thereciprocating movement of the bed 11.

Thus, it will be apparent that each time the bed 11 moves on itsprinting stroke, which is to the right as viewed in Figure 1, the member21 will be rotated counter-clockwise to the position illustrated inorder to move the impression cylinder to its impression position wherein the cylinder bearers 29 are brought into contact with the bed bearers31 under a predetermined pressure. As the bed commences its returnstroke, the member 21 is rotated clockwise whereby to break the toggleand permit the cylinder to raise to its inoperative position to provideclearance for the form.

From the description thus far it is evident that each I time theactuating member 21 is oscillated, the impression cylinder is movedthrough a fixed distance, vertically and the extent of such movement issubstantially equivalent to the distance between the respective axes Aand B. Therefore, in order to vary the degree of pressure exertedbetween the respective impression cylinder and bed bearers when in theimpression position, the vertical position of the control block 22 mustbe adjusted accordingly in order to raise and/or lower the axis ofrotation of the cylinder actuating member 21.

As shown in Figure 1, the control block is adjustably mounted in anopening 32 provided therefor in the cap member 33 and the side walls 34of said opening constitute guides which are adapted to fit intocorresponding grooves formed in the side walls of the control block soas to prevent any lateral movement thereof but which permit the block tobe adjusted vertically.

The vertical position of the control block 22 is readily adjustable andit is maintained in its adjusted position by means of a pressure controlmember 36 which is rotatably mounted in the cap member 33 with its axiscoincident with a vertical plane through the axis of the journal 15. Thepressure control member is provided with concentric bearing surfaces 37along its lateral edges which engage the frame member 33, see Figure 2,and which are separated by an intermediate curved surface 38, the axisof which is eccentric with respect to the axis of the bearing surfaces.The eccentric surface has coaction with an adjustment block 39 arrangedintermediate the pressure control member 36 and the control block 22,whereby to adjust the vertical position of said control block uponrotation of the member 36. The adjustment block 39 is seated on thecontrol block 22 and its upper edge is formed so as to correspond incurvature with the eccentric surface 38. Thus when the member 36 isrotated the eccentric surface 38 thereof effects a correspondingvertical displacement of the control block 22 which in turn lowers orraises the axis of rotation of the actuating member 21 to therebyincrease or decrease the pressure relation between the bed and cylinderin the impression position.

The pressure control member 36 is adapted to be rotated in the capmember 33 whereby to vary the angular position of its eccentric surface38 by means of two tension rods 41 and 42 one of which is pivotallyconnected to said member on each side of the axis thereof. The member 36is grooved to accommodate the tension rods which project upwardlythrough aligned openings 44 and 45 formed in the cap member 33 and thefree ends thereof project beyond said member and are threaded to receivethe adjustable nuts 46 and 47. Bushings 48 and 49 are seated in theupper ends of the openings in the cap member to provide seats againstwhich the respective nuts coact to effect adjustment of the member 36.

Thus it will be seen that by loosening one of the nuts 46 or 47 andtightening the other, the pressure control member 36 can be rotated ineither direction about its axis in the cap member whereby to vary theangular position of the eccentric surface 38. This in turn effects acorresponding vertical displacement of the adjustment block 39 andtherewith the control block 22 which in turn raises or lowers the axisof rotation of the member 21 to thereby increase or decrease thepressure relation between the cylinder and the bed in their operativeposition.

To provide for convenient assembly and disassembly of the mechanism, thetension rods are connected to the pressure controlmember 36 by means ofclevis pins 43 which are inserted in the horizontal openings providedtherefor in the control member 36 so as to project through the eyes inthe depending ends of the tension rods. Each pin is formed with areduced diameter neck 51 adjacent one end thereof and when they areplaced in position they are located so that the said neck portion isadjacent the end face of the control member 36. The pins are locked inposition by means of a plate 52 the edge of which is-adapted to fit intothe neck portion 51 of the pins 43 and which plate is then secured tothe control member by means such as the bolts 53. Thus the pins arenormally retained against axial displacement but can readily be removedby loosening the bolts 53 and removing the plate 52.

The extent of the adjustment imparted to the pressure control member 36at each end of the impression cylinder can be readily determined bymeans of an indicator 54 which is secured to the outer face of thecontrol member 36 and is adapted to register on a scale 55 fixed to thecap member 33. The scale 55 preferably is calibrated with relation tothe eccentric surface 38 and is adapted to register the extent of theadjustment in increments of .001 of an inch.

Thus it is a relatively simple matter to effect corresponding,infinitely variable precision pressure adjustments at each end of theimpression cylinder and since the adjusting members are readilyaccessible such adjustments can be accomplished in a minimum of time.

The tension rods 41 and 42 are also utilized to lock the pressurecontrol member in its adjusted position and to preload or precompresssaid member against the force of impression. As stated above, when anadjustment is to be made, one of the adjusting nuts 46 or 47 is loosenedwhereupon the other is tightened against its respective bushing 48 or 49to effect partial rotation of the control member 36. After theadjustment is completed, the nut which originally was loosened is drawnup tight and sufficient tension is applied whereby any clearanceexisting between the top surface of the pressure control member 36 andthe cap member 33 is removed and said members are actually precompressedagainst the force of impression.

This represents a decided advantage over the known pressure controldevices because it makes possible a substantial reduction in the overallclearances which must be taken up and the number of members which mustbe compressed during the short interval after the bed bearers 56 engagethe cylinder bearers 29 and before the leading edge of the form 12reaches the point of impression. Thus the movement of the cylinder uponengaging the bed bearers will be suflicient to take up any remainingclearances between the other control members such as 21, 22 and 39during the short interval provided for this purpose and, since thecontrol member 36 is already precompressed, any relative movement of thecylinder resulting from compression of the other members after theimpression commences will be so minute as to have little or no effectupon the printed impression.

Having thus disclosed a preferred embodiment of my invention, I claim:

1. In a printing press or like machine having a frame, an impressioncylinder rotatably mounted in said frame for bodily movement betweenoperative and inoperative impression positions with relation to areciprocating bed, and mechanism including a toggle member-for movingthe cylinder between said positions, the combination comprising anadjustable control block having co-action with said toggle member toproduce a predetermined pressure between the bed and cylinder when thelatter is in its operative impression position, a cylindrical elementmounted for partial rotation in said frame about an axis located abovesaid control block, said cylindrical element having an eccentric surfaceformed integral therewith for adjusting the position of :said controlblock upon rotation of said element whereby to vary the pressure betweenthe bed and cylinder when said cylinder is in its operative impressionposition, link means pivotally connected to said cylindrical element andextending through openings in the frame, and manually operable meansengaging said link means and having co-action with the frame, saidmanually operable means being adapted to be operated for first rotatingsaid element to eifect adjustment of said control block and thereafterbeing operable to preload said element against the force exerted whenthe cylinder is in its impression position.

2. In a printing press or like machine having a frame, an impressioncylinder rotatably mounted in said frame for bodily movement betweenoperative and inoperative impression positions with relation to areciprocating bed, and mechanism including a toggle member for movingthe cylinder between said positions, the combination comprising anadjustable control block having coaction with said toggle member toproduce a predetermined pressure be tween the bed and cylinder when thelatter is in its operative impression position, a cylindrical elementmounted for partial rotation in said frame about an axis located abovesaid control block, said cylindrical element having an eccentric surfaceformed integral therewith for adjusting the position of said controlblock upon rotation of said element whereby to vary the pressure betweenthe bed and cylinder when said cylinder is in its operative impressionposition, a pair of tension rods pivotally connected to said cylindricalelement at diametrically opposite locations, said rods extendingupwardly in parallel relation and extending through openings in theframe, and adjustable means threadedly engaging the projecting ends ofthe rods respectively and having co-action with the frame, wherebyrotation of said respective adjustable means to tighten one and loosenthe other will impart rotary motion to said element and whereby rotationto tighten both said adjustable means will preload said element againstthe force exerted when the cylinder is in its impression position.

3. In a printing press or like machine having a frame, an impressioncylinder rotatably mounted in said frame for bodily movement betweenoperative and inoperative impression positions with relation to areciprocating bed, and mechanism including a toggle member for movingthe cylinder between said positions, the combination comprising anadjustable control block having coaction with said toggle member toproduce a predetermined pressure between the bed and cylinder when thelatter is in its operative impression position, a rotatable elementseated in the frame, means formed integral with said element foradjusting the position of the control block upon rotation of saidelement whereby to vary the pressure between the bed and cylinder whensaid cylinder is in its operative impression position, and manuallyoperable means including members p-ivotally connected to said elementand having coaction with the frame for first rotating said element toefiect adjustment of said control block and for thereafter compressingsaid element against the frame and in the direction of the force exertedon said element when the cylinder is in its impression position, tothereby reduce the relative movement of said cylinder resulting fromcompression and expansion of the said element and said frame as thecylinder goes on and off impression.

References Cited in the file of this patent UNITED STATES PATENTS1,019,253 Hodgman Mar. 5, 1912. 1,380,469 Droitcour June 7, 19211,562,775 Leilich Nov. 24, 1925 2,079,001 Crafts May 4, 1937 2,743,672Harless et al. May 1, 1956

